title: Water column monitoring of the biological effects of produced water from the Ekofisk offshore oil installation from 2006 to 2009.
abstract: The Norwegian water column monitoring program investigates the biological effects of offshore oil and gas activities in Norwegian waters. In three separate surveys in 2006, 2008, and 2009, bioaccumulation and biomarker responses were measured in mussels (Mytilus edulis) and Atlantic cod (Gadus morhua) held in cages at known distances from the produced water (PW) discharge at the Ekofisk oil field. Identical monitoring studies performed in all three years have allowed the biological effects and bioaccumulation data to be compared, and in addition, enabled the potential environmental benefits of a PW treatment system (CTour), implemented in 2008, to be evaluated. The results of the 2009 survey showed that caged animals were exposed to low levels of PW components, with highest tissue concentrations in mussels located closest to the PW discharge. Mussels located approximately 1-2 km away demonstrated only background concentrations of target compounds. Concentrations of polycyclic aromatic hydrocarbons (PAH) and alkyl phenol (AP) metabolites in the bile of caged cod were elevated at stations 200-250 m from the discharge. There was also a signal of exposure relative to discharge for the biomarkers CYP1A in fish and micronuclei in mussels. All other fish and mussel biomarkers showed no significant exposure effects in 2009. The mussel bioaccumulation data in 2009 indicated a lower exposure to the PW effluent than seen previously in 2008 and 2006, resulting in an associated general improvement in the health of the caged mussels. This was due to the reduction in overall discharge of PW components (measured as oil in water) into the area in 2009 compared to previous years as a result of the improved PW treatment system.
authors.affiliation: Norwegian Institute for Water Research (NIVA), Oslo, Norway. sbr@niva.no
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Brooks
authors.forename: Christopher
authors.initials: C
authors.lastname: Harman
authors.forename: Merete
authors.initials: M
authors.lastname: Grung
authors.forename: Eivind
authors.initials: E
authors.lastname: Farmen
authors.forename: Anders
authors.initials: A
authors.lastname: Ruus
authors.forename: Sjur
authors.initials: S
authors.lastname: Vingen
authors.forename: Brit F
authors.initials: BF
authors.lastname: Godal
authors.forename: Janina
authors.initials: J
authors.lastname: Barsiene
authors.forename: Laura
authors.initials: L
authors.lastname: Andreikenaite
authors.forename: Halldóra
authors.initials: H
authors.lastname: Skarpheðinsdottir
authors.forename: Birgitta
authors.initials: B
authors.lastname: Liewenborg
authors.forename: Rolf C
authors.initials: RC
authors.lastname: Sundt
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000097:blood / Q000378:metabolism; D001822:Body Burden; D019363:Cytochrome P-450 CYP1A1 / Q000378:metabolism; D004527:Egg Proteins / Q000097:blood; D004784:Environmental Monitoring / Q000379:methods*; D019652:Extraction and Processing Industry; D005260:Female; D048389:Gadus morhua / Q000097:blood / Q000378:metabolism*; D005982:Glutathione Transferase / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008297:Male; D049880:Mytilus edulis / Q000187:drug effects* / Q000378:metabolism; D009664:Norway; D010578:Petroleum; D011084:Polycyclic Aromatic Hydrocarbons / Q000378:metabolism; D012623:Seawater / Q000737:chemistry; D014819:Vitellogenins / Q000097:blood; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity*
chemical_list: D015415:Biomarkers; D004527:Egg Proteins; D010578:Petroleum; D011084:Polycyclic Aromatic Hydrocarbons; D014819:Vitellogenins; D014874:Water Pollutants, Chemical; C423083:zona radiata protein, fish; D019363:Cytochrome P-450 CYP1A1; D005982:Glutathione Transferase